The invention relates generally to nano-cellular polymer foams and methods for making them. Further, the invention relates to articles made from the nano-cellular polymer foams.
Polymeric foams are generally used primarily for their cushioning effect, and secondarily for beneficial effects arising out of their structural aspects, such as for example, ability to absorb liquids or energy, thermal insulation, etc. Growing environmental concern and improved performance requirement at a lower weight is a constant research thrust for foam and other materials. The tunable pore morphology of polymeric foams for enhanced properties has not been fully exploited for improving the performance. Currently polymeric foam is dominated by commodity polymers with structural property less than or with in the theoretically possible upper and lower bounds. It is known in the art that reducing the pore size and variation to micrometer level can bring the properties within the lower and upper bounds of classical entitlement. There is a continued need for improving the properties to above the classical upper bound theory while keeping the material weight as low as possible. In summary, this invention is about engineered polymeric foam morphology with superior structural, thermal and dielectric properties and is transparent.
Therefore, there is a need for nano-cellular polymer foams having enhanced properties, and methods for making the foams.